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Any idea of a CP/M Disk ID?

Chuck(G)

Chuck(G)

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I received a few 3.5" DSHD floppies with no clues as to what the system they came from might be.

They're 80 cylinder, double-sided 9 sectors of 1,024 bytes; i.e 1440K. So they're not just some 8" drive format placed onto 3.5" disks (an 8" track is shorter). These appear to be mostly data disks, so no clue on the system, except for one that contains the word "MAGNUM" in the first sector of cylinder 0.

Does this sound familiar to anyone? It'd be a CP/M system from the 1990s, given the medium.
 
Plenty of non-PC devices used 3.5" floppy drives with proprietary disk formats: word processors, synthesizer keyboards, digital oscilliscopes, car engine diagnostic computers, etc....
 
I didn't say this was a PC--my guess it might be from an NCR 3000-series. That's just a wild stab, though.

But this is definitely a CP/M format. Don't you think so? Here's a 256-byte sample.

Code: 
00004800  00 43 49 55 44 41 44 45  53 4e 58 31 00 00 00 1a  |.CIUDADESNX1....|
00004810  05 00 06 00 00 00 00 00  00 00 00 00 00 00 00 00  |................|
00004820  00 46 49 53 49 43 4f 39  31 54 58 54 00 00 00 80  |.FISICO91TXT....|
00004830  07 00 08 00 09 00 0a 00  cf 00 d0 00 d1 00 d2 00  |................|
00004840  00 43 4c 41 53 45 53 20  20 4e 58 33 00 00 00 32  |.CLASES  NX3...2|
00004850  0b 00 0c 00 0d 00 0e 00  00 00 00 00 00 00 00 00  |................|
00004860  00 43 4c 49 45 4e 54 45  53 44 49 52 00 00 00 80  |.CLIENTESDIR....|
00004870  0f 00 10 00 11 00 12 00  13 00 14 00 15 00 16 00  |................|
00004880  00 43 4c 49 45 4e 54 45  53 44 49 52 01 00 00 80  |.CLIENTESDIR....|
00004890  17 00 18 00 19 00 1a 00  1b 00 1c 00 1d 00 1e 00  |................|
000048a0  00 43 4c 49 45 4e 54 45  53 44 49 52 02 00 00 80  |.CLIENTESDIR....|
000048b0  1f 00 20 00 21 00 22 00  23 00 24 00 25 00 26 00  |.. .!.".#.$.%.&.|
000048c0  00 43 4c 49 45 4e 54 45  53 44 49 52 03 00 00 80  |.CLIENTESDIR....|
000048d0  27 00 28 00 29 00 2a 00  2b 00 2c 00 2d 00 2e 00  |'.(.).*.+.,.-...|
000048e0  00 43 4c 49 45 4e 54 45  53 44 49 52 04 00 00 80  |.CLIENTESDIR....|
000048f0  2f 00 30 00 31 00 32 00  33 00 34 00 35 00 36 00  |/.0.1.2.3.4.5.6.|

I imagine that the file "FISC091.TXT" refers to 1991, which would make my guess about the age more or less correct. I've extracted files from most of them, but have only customer data, no other hints or programs.
 
I'm not that familiar with the CP/M file system to be honest so sorry for the uneducated guess but is it layed out like FAT-12? File name then sectors used? Looks like CLIENTESDIR at least is taking up multiple FAT entries but the sectors are fairly contiguous. Is there corresponding text for that? Your the expert though so I'm sure you already did all this lol. The only other thing I'd try is get the strings output of the disk dump. See if you end up seeing any useful words although it looks like they may be in spanish.
 
lol doing some google translating of the ciudades file name different seperation comes up with different interesting but probably misleading results. Ciu dades seems to translate to "city data" in "Catalon"
 
I unraveled the file system and can read the darned things, (some sort of database; one disk has source code for what I think is the program that handles this (Pascal)). Mostly inventory and contact information--and yes, it's Spanish.

But I still don't know what machine created these floppies.

I'm known to have a certain familiarity with 22DISK. :)
 
barythrin said:
lol doing some google translating of the ciudades file name different seperation comes up with different interesting but probably misleading results. Ciu dades seems to translate to "city data" in "Catalon"
Click to expand...

In Spanish, it means "cities". Ciudades.
 
Well, digging through the disks, the disk format appears to be from a Magnum CP/M CBIOS, running on a Holmes VID80 board, in a TRS-80 model III with a customer mod to use 1.44M HD floppies.

Clearly, this one will NOT go into 22Disk.
 
The CBIOS contains definitions for 8" DSDD; the user evidently tacked on 3.5" HD floppy drive and lengthened the track a bit. I've done this with a Model 16 myself. I'm guessing about the Model III--but VID80 is definitely mentioned.
 
Strange. I wonder if it might have been a Model I + VID80 + Holmes Expansion Interface; the ads for the Holmes disk controller touted its ability to handle 8" floppy drives? (It occurred to me after posting that hardware like that existed but I've never seen it in action; I remember there was a companion board for the Omikron mapper for using 8" drives and some of the ads for double-density boards also claimed the ability to use 8" disks, but... is it just cabling to use an 8" floppy on a III/4 or do you need a special controller there as well? If it is just cabling it might be interesting to see if a software patch to TRS-DOS to fully utilize a 1.44mb floppy is possible.)

In any case, that's an amazingly weird disk format to run into. If the data on the disk were in Portuguese* instead of Spanish I'd wonder if they might be from some really weird Brazilian clone that incorporated a VID80 compatible CP/M mode.

(* Edit: It is notable that "cliente" is Portuguese for "client"...)
 
I can tell you that the content of disks is in Spanish. Não português (which to me, looks like badly-spelled Spanish. I suppose that the Portuguese think similarly of the Spanish).

If you can read and write 8" double-density floppies, then 1.44M 3.5" floppies are a walk in the park.
 
Not just high, but the same data rate as 8" floppies. The big difference is that 8" spins at 360 RPM and the 1.44 3.5" spins at 300 RPM. So time-wise, a track on the 3.5" HD drive is longer.

To be complete, many "3-mode" capable 3.5' drives can also be made to spin at 360 RPM. This, and the 5.25" HD format makes a nice "shrinkage" pattern--NEC, for instance, recorded the same format on 8", 5.25" and 3.5" floppies.
 
Yeah. I just wonder if the 8" data rate is an "undocumented feature" of the standard TRS-80 Model III/4 controllers or if you'd have to have a third party controller to write this format. (8" drives were such rare birds on the "little" TRS-80s it's not the sort of information that seems to be floating around in easily searched forms.)
 
So what gave all that information away? Out of curiosity is there any sort of intelligence one could make from flux patterns or would that be more unique per drive or too generic and just file system based?
 
Not being a RS follower, I can't say for certain--but surely someone here knows everything that there is to know about the Model III/4 boxes.
 
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